If you reside in the warm and humid areas of the country, such as here in Texas, you may have noticed that the shingles on your roof have developed streaks and stains. Although these stains and streaks may appear to be mold at first glance, they are most often a type of blue-green algae,  Or, in more familiar terms, a form of moss.

In some very small cases, the streaks may be mold, and if so, this can prove very dangerous for your family, not to mention much more difficult to get rid of.  If the stains are mold, then you or your family members may start suffering from asthma, headaches, and various other medical conditions. Fix the small roof problems early to prevent them from becoming a serious issue. Knowing the difference between the two and how to properly treat the problem is imperative.


By its very nature, algae of all kinds will grow and thrive flush and low to the surface it chooses to take up residence on.  With this in mind, if you see dark streaks on your roof, the chances are pretty good that they are caused by algae buildup.

Algae can develop anywhere the conditions are right and is usually spread from one location to another by the wind, wild birds, and the occasional varmint.  Algae affect many homes across most of the United States due to its ease of spreading.

The life cycle starts airborne, with the spores that will float on the wind in most cases and land on your roof.  If you have an asphalt roof with a northern exposure, you will most likely have to deal with the development of algae.


If the areas of your roof are green and fuzzy in appearance, then you most likely do not have algae but instead moss.  Moss, unlike algae, prefers those areas that are damp and cool, such as shaded areas that allow moisture to linger.  Prime conditions for moss to grow and thrive.

Moss is also spread through the air, via its spores, much like algae is.  Once the spores have found their way onto your roof, they will take up residence in the space between the shingles and begin the grow and thrive into a mass of thick fuzzy moss.


Although moss and algae are typically grouped together, and they both will grow on your roof, they are actually distinct and different from one another.  While moss presents with the appearance of being fluffy and green, algae typically appear in a variety of colors such as green, blue, brown, or gray. Moss will also grow upward from your roof, which algae will remain flat and hug the shingles.


Remember that we do not recommend you attempt to remove any roof moss or algae yourself.  You will not want to see it as a DIY situation, and we highly advise you to reach out to a professional to get the job done.  If you attempt to DIY the removal yourself, there are a few things to remember.

There are products on the market geared toward situations like this, with some even billed as environmentally friendly.  The products are generally available at most hardware stores and applied with a sprayer on the end of a standard garden hose.  Although the method is safe, it can often take 3-6 months to see results when applied correctly.

If you are looking for a somewhat more aggressive method that could yield faster results, you could try using a mixture of water and bleach to tackle the problem.

  1. Mix one part water with one part oxygen bleach cleaner

  1. Pour the mixture on the areas of the roof affected and let it sit for at least 30 minutes

  1. After 30 minutes, rinse the solution off with your hose on low pressure.  DO NOT pressure wash your roof.  It will take several days for the moss to dry up and blow off your roof in the wind.


The best method for preventing the buildup of moss or algae on your roof is to take steps to avoid it in the first place.  Keep the trees near your home trimmed, such as those that tend to hang over your roof, and do not let water stand on those roofs that are flat.

Service First Construction Group: Your Trusted Roof Cleaning Professionals in Texas

Service First Construction Group is your go-to expert for roof cleaning services in Texas's warm and humid areas. With years of experience, we understand the unique challenges of algae and moss growth on roofs. Whether it's streaks caused by algae or fluffy moss in shaded areas, our professional team knows how to tackle the problem safely and effectively.

Instead of risking DIY solutions, Service First Construction Group recommends contacting our experts for a thorough and reliable roof cleaning experience. Don't let moss and algae damage your roof or affect your family's health. Trust the best roofer in Tomball, Tx, to keep your roof clean and in top condition, allowing you to enjoy a safe and beautiful home.

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Our object in the construction of the state is the greatest happiness of the whole


CEO at Compaxit
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Our object in the construction of the state is the greatest happiness of the whole

MARIA Norton

CEO at Compaxit

What thay say

Our object in the construction of the state is the greatest happiness of the whole, and not that of any one class.

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